In the prior art, it is known that digital recordings, such as compact disks (CD), are not reproduced with the same sound volume for a specified sound setting level. This is essentially due to the type of music and the way in which the piece of music was recorded. Indeed, a sound frame is composed of an electrical signal comprising a succession of oscillations and peaks. Each peak corresponds to a voltage value. The higher the voltage in terms of absolute value, the higher the volume and the higher the slope of the signal variation, the higher the frequency of the sound reproduced. When such a recording is recorded in the form of a digital file and then reproduced on a sound system by means of a digital sound card on a computer, the same maximum variation phenomena are observed since the data contained in the file is approximately the same as that recorded on a CD. Consequently, between two recordings of different types of music, it is necessary to modify the sound level setting between two recordings, to obtain a reproduction with the same sound level for two different recordings with different original sound levels.